(57) A receiver is synchronised to a signal by studying which among the previously calculated
responses to known synchronisation errors corresponds to the response of a real, received
signal. A sample sequence decimated from an oversampled signal is compared to model
sequences which correspond to decimation at a different distance from the optimum
decimation point, and in further processing the employed decimation point is used
according to how far from optimum the best correlated model sequence is situated.
From the phase angles of the samples, there is calculated an average phase angle change
per symbol, and on the basis of that and the known symbol rate, the frequency error
in the reception is determined. For each sample of the data burst, there is calculated
an individual phase correction by multiplying the individually defined average phase
shift per symbol by the distance from a given symbol corresponding to a phase reference
value, and by adding the result to said phase reference value. Bursts are received
in groups, and timing and frequency errors are predicted on the basis of the trends
indicated by preceding groups in order to receive the next group. A unit formed of
several groups is used for measuring and predicting the change in the doppler frequency.
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